Firstly: Take your time
There is a lot of content/training to cover! Don't try and pack it all into a short amount of time. Spend 5-10 hrs a week completing the training material, over a few weeks. Trying to pack it all into a short intense period doesn't work.
Complete the key courses. I found completing them in the following order worked best for me:
Optimizely Content Cloud Development Fundamentals
Episerver CMS - Advanced Development
Implementing Headless Using Optimizely Content Delivery API
Episerver CMS - Reviewing Development Fundamentals
Episerver CMS - Certification Exam Preparation
After sitting the exam myself. I would also recommend completing the following optional courses on DXP (DXC) as there seem to be quite a few questions on DXP
DXP Cloud Hosting Technical Review
Developing for DXC Service
Other areas to focus on are:
The most useful documents from the academy I found were the practice questions (159 at time of writing), and the study guide. The practice questions I tried to complete in 'exam conditions'. To give me a gauge on where I was sitting in comparison to the pass mark. I then went through the ones I got wrong and hit either Google or the academy to do some research and understand why I got it wrong. I then went through the study guide and researched the gaps in my knowledge, on Google, but also on the academy.
N.B. The practice questions are slightly more difficult. As they are worded like 'select all the right answers' or 'select the relevant answers'. The questions I got on the actual exams I got were all 'Select the 2/3/n right answers'. Which I found easier to answer. - Update: I've been informed by someone else who sat the exam recently, the they got a couple of "select the relevant answers" style questions.
The exam is broken up into 5 sections, each with a different balance of questions
Product Knowledge (17%)
Installation, Operation and Configuration (17%)
Content Models (32%)
Creating Websites (21%)
Advanced Concepts (13%)
Another N.B. There still some practice questions (and information on Google) about XForms, but XForms are no longer in the exam. Content Delivery API is covered in the Content Models section.